JP2012070300A - Imaging apparatus and control method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control projection of a captured image so as not to obstruct an imaging situation.SOLUTION: An imaging part (101) captures an image of a subject and a projection part (110) projects an image captured by the imaging part (101). A system control unit (116) controls the imaging part (101) and the projection part (110) according to the imaging mode. In a candle light mode among imaging modes, the system control unit (116) reduces a shutter speed of the imaging part (101) to increase an AGC gain and makes the light quantity projected by the projection part (110) lower than a reference value or turns the light off.

Description

  The present invention relates to an imaging apparatus and a control method thereof, and more specifically to an imaging apparatus having an image projection function and a control method thereof.

  2. Description of the Related Art Conventionally, an imaging device including an image projection device such as a projector is known. This type of imaging apparatus can project and shoot a captured image on an arbitrary place.

  Japanese Patent Application Laid-Open No. 2004-228561 describes an imaging apparatus that assists photographing by simultaneously performing projection during image photographing. The imaging device described in Patent Document 1 projects a preview image of a subject, and thus a person who is a subject can visually recognize how the subject is photographed.

JP 2006-80875 A

  The imaging apparatus described in Patent Document 1 performs the same processing regardless of the shooting environment (and projection environment). Accordingly, there is a problem that the projection light or its reflected light interferes with the subject when the amount of ambient light is smaller than the amount of projection light. For example, when a preview image is projected in a situation where a subject under the illumination light of a candlelight is imaged, reflected light of the projected light may interfere with the subject. If the amount of projection light is large, the subtle atmosphere of the candlelight will be impaired.

  An object of the present invention is to present an imaging apparatus and a control method therefor that can eliminate such inconvenience.

  An imaging apparatus according to the present invention projects an imaging unit capable of changing an imaging condition including an exposure amount and a zoom, an image processing unit that performs image processing on an image captured by the imaging unit, and an image processed by the image processing unit. Projecting means, operating means for instructing one of a plurality of imaging modes, and controlling the imaging conditions of the imaging means according to the imaging mode specified by the operating means, and image processing conditions of the image processing means And a control unit that controls any of the projection conditions of the projection unit, wherein the control unit reduces the projection light amount of the projection unit below a reference value in a candlelight imaging mode. It is characterized by.

  An imaging apparatus according to the present invention projects an imaging unit capable of changing an imaging condition including an exposure amount and a zoom, an image processing unit that performs image processing on an image captured by the imaging unit, and an image processed by the image processing unit. A projecting unit; a unit that determines an imaging mode from an image captured by the imaging unit; and the imaging condition of the imaging unit is controlled according to the determined imaging mode, and the image processing condition of the image processing unit and the An image pickup apparatus having a control unit that controls any one of the projection conditions of the projection unit, wherein the control unit reduces a projection light amount of the projection unit below a reference value in a candlelight imaging mode. And

  An image pickup apparatus control method according to the present invention includes an image pickup unit that can change an image pickup condition including an exposure amount and a zoom, an image processing unit that performs image processing on an image captured by the image pickup unit, and an image processed by the image processing unit. A method for controlling an imaging apparatus including a projecting unit that projects a plurality of imaging modes, the imaging condition of the imaging unit according to the designated imaging mode, and A step of controlling any one of the image processing conditions of the image processing means and the projection conditions of the projection means, and in the candlelight imaging mode, the step of reducing the projection light amount of the projection means to be less than a reference value. It is characterized by that.

  An image pickup apparatus control method according to the present invention includes an image pickup unit that can change an image pickup condition including an exposure amount and a zoom, an image processing unit that performs image processing on an image captured by the image pickup unit, and an image processed by the image processing unit. A method for controlling an imaging apparatus comprising: a projecting unit that projects an image; and a step of determining an imaging mode from an image captured by the imaging unit, and the imaging condition of the imaging unit according to the determined imaging mode And controlling either of the image processing conditions of the image processing means and the projection conditions of the projection means, and in the candlelight imaging mode, reducing the projection light quantity of the projection means below a reference value; It is characterized by comprising.

  According to the present invention, by controlling the projection conditions according to the imaging mode, it is possible to perform imaging without losing the atmosphere of the subject and to check the imaging angle of view.

It is a schematic block diagram of the first embodiment of the present invention. It is a table | surface which shows the imaging control corresponding to the imaging mode in a present Example. It is a figure which shows the gamma characteristic of a present Example. It is a table | surface which shows the projection control corresponding to the imaging mode in a present Example. It is an example of the projection image of a present Example. It is a schematic block diagram of the second embodiment of the present invention. It is a figure explaining the imaging scene discrimination | determination method of 2nd Example. It is a control flowchart of a 2nd example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a schematic block diagram of an embodiment of an imaging apparatus according to the present invention. The imaging unit 101 includes an imaging optical system 102, an imaging element 103, and an imaging system image processing unit 104. The imaging optical system 102 includes an optical lens and a diaphragm. The image sensor 103 converts a subject optical image incident through the imaging optical system 102 into an electrical signal. The imaging system image processing unit 104 performs video signal processing such as gamma correction, white balance, and edge enhancement on the image signal from the imaging element 103.

  Reference numeral 105 denotes an imaging mode management unit that manages information related to imaging modes described later. Reference numeral 106 denotes a liquid crystal driving unit for causing the liquid crystal panel 107 to form an image of the captured image data output from the imaging system image processing unit 104. Reference numeral 107 denotes a liquid crystal panel for displaying an image on the image pickup apparatus main body.

  108 represents the captured image data output from the imaging system image processing unit 104 as JPEG or H.264. A recording control unit that performs encoding according to an encoding method such as H.264 and the like and records the information on the recording medium 109 according to a predetermined file system. A recording medium 109 includes an HDD (hard disk), a memory, and the like, and records an output signal of the recording control unit 108.

  Reference numeral 110 denotes an image projection unit. A projection system image processing unit 111 performs processing such as gamma correction, edge enhancement, and edge imaging described later on input image data.

  A liquid crystal driving unit 112 drives the liquid crystal panel 114 to display an image based on the input image data. Reference numeral 113 denotes a light source that supplies light to the liquid crystal panel 114. Reference numeral 114 denotes a liquid crystal panel.

  Reference numeral 115 denotes a projection optical system that includes a zoom lens, a focus lens, and the like and projects an optical image obtained by supplying projection light from the light source 113 to the liquid crystal panel 114 on a projection surface (not shown).

  Reference numeral 116 denotes a system control unit that controls the entire imaging apparatus. Reference numeral 117 denotes an operation unit that receives an operation from the user. The system control unit 116 can control the imaging conditions of the imaging unit 101, for example, the exposure amount and the zoom. The system control unit 116 can also control projection conditions of the projection unit 110 such as the image processing conditions of the projection system image processing unit 111 and the light amount of the light source 113, that is, the projection light amount.

  In the imaging apparatus shown in FIG. 1, a basic operation when projecting a photographed image at the time of photographing will be described.

  The subject optical image incident on the image sensor 103 through the imaging optical system 102 is photoelectrically converted, amplified to an appropriate level by an AGC amplifier (not shown), and then output to the imaging system image processing unit 104. The imaging system image processing unit 104 performs various image processing such as gamma correction, color correction, and edge enhancement processing on the image signal generated by the imaging element 103. The liquid crystal driving unit 106 converts the image signal into a format suitable for forming an image on the liquid crystal panel 107 and outputs the converted signal. The recording control unit 108 performs a predetermined encoding process such as JPEG on the image signal output from the imaging system image processing unit 104, and then records the image signal on the recording medium 109.

  The imaging system image processing unit 104 also outputs the image data to the projection unit 110. The projection unit 110 projects the image data from the imaging system image processing unit 104 onto a projection plane (not shown).

  The processing of the projection unit 110 will be described in detail. The projection system image processing unit 111 performs image processing such as gamma processing, color correction, contour enhancement, and edge imaging described later on the image signal output from the imaging system image processing unit 104. In addition, conversion to a resolution suitable for the liquid crystal panel 114 is performed, and an image signal is output to the liquid crystal driving unit 112. The liquid crystal driver 112 converts the image signal into a format suitable for image formation on the liquid crystal panel 114 and outputs it to the liquid crystal panel 114.

  The image formed on the liquid crystal panel 114 is converted into a projected image by modulating the luminance of the illumination light from the light source 113. The projection optical system 115 projects a projection image formed by the liquid crystal panel 114 onto a projection surface (not shown).

  Although the case where the captured image is projected by the projection unit 110 simultaneously with the imaging is described, the same processing is performed in the projection unit 110 when the image signal stored in the recording medium 109 is projected and displayed.

  Processing at the time of switching the imaging mode will be described. The imaging apparatus of the present embodiment has a plurality of imaging modes. The user can instruct the imaging control mode to the system control unit 116 through the operation unit 117. When the user instructs the operation unit 117 to change the imaging mode, the system control unit 116 outputs the switched new imaging mode information to the imaging mode management unit 105. The system control unit 116 refers to the imaging mode information managed by the imaging mode management unit 105 and controls the imaging unit 101 and the projection unit 110.

  In this embodiment, there are four imaging modes: a candlelight mode, a low illumination mode, a night view mode, and a landscape mode. In each imaging mode, it is possible to specify whether or not a person is included as a subject.

  A control process of the imaging unit 101 by the system control unit 116 in each imaging mode will be described. FIG. 2 is a table showing processing of the imaging unit 101 corresponding to the four imaging modes.

  In the candlelight mode, the system control unit 116 increases the sensitivity by reducing the shutter speed of the image sensor 103 and increasing the AGC gain (not shown). Further, the white balance in the imaging system image processing unit 104 is adjusted to sunlight (about 5000K). As a result, it is possible to perform imaging while leaving the atmosphere such as redness of candlelight without using strobe light.

  In the low light mode, the AGC gain is further increased than in the candle light mode, and the shutter speed is decreased to increase the sensitivity. This makes it possible to take a bright image even in a dark place.

  In the night view mode, different processing is performed depending on whether the subject includes a person or not. If a person is included, the same processing as in the low light mode is performed. When a person is not included, the AGC gain is set to the standard state, and the gamma characteristic in the imaging system image processing unit 104 is switched to a characteristic that does not excessively increase the luminance in the dark part. The gamma characteristic is shown in FIG. FIG. 3 shows the input / output characteristics (gamma characteristics) of the luminance of the input image signal. 3A shows the gamma characteristic in the standard state, and FIG. 3B shows the gamma characteristic in the night view mode (without people). As shown in FIG. 3B, the gradation of the dark part is crushed and made to feel like it is. As a result, it is possible to prevent the dark portion of the night view from being corrected excessively brightly, and to reproduce the darkness with less roughness and tightened black.

  In the landscape mode, processing for increasing the strength of the edge enhancement processing in the imaging system image processing unit 104 and increasing the color saturation is performed. Further, the gamma characteristic is changed to increase the contrast as shown in FIG. By increasing the contrast as shown in FIG. 3 (c), it becomes possible to depict the landscape more stereoscopically and vividly.

  Processing of the projection unit 110 in each imaging mode will be described. FIG. 4 is a table showing the control content of the projection unit 110 by the system control unit 116 according to the imaging mode.

  As described above, the user can specify whether the scene includes a person in addition to the imaging mode. When the user designates “does not include a person”, the projector enters another mode that does not include a person, and the projection unit 110 does not perform projection. This is because there is no person who should confirm the image even if the projection is performed. On the other hand, when “include a person” is designated, the system control unit 116 controls the projection optical system 115, the light source 113, and the projection system image processing unit 111 according to the designated imaging mode, as described below. .

In the candlelight mode, the system control unit 116 controls the light amount of the light source 113 to be lower than a reference value. Further, the projection system image processing unit 111 is controlled to perform edge imaging. The edge image will be described with reference to FIG. FIG. 5A shows an example of a captured image output from the imaging system image processing unit 104. FIG. 5B shows an edge image obtained by first-order differentiation in the horizontal direction with respect to the image output from the imaging system image processing unit 104. In the case of a digital image signal, it is known that the primary part can be expressed by a difference. That is, if f (i, j) is a light and shade level at the coordinates (i, j) of the image, the edge image is
Δf (i, j) = f (i + 1, j) −f (i−1, j)
It is expressed by FIG. 5B shows an example in which Δf (i, j) is imaged as a luminance value.

  Further, the system control unit 116 controls the color temperature control unit included in the projection system image processing unit 111 to bring the color temperature of the projection light closer to the color temperature of the subject light source. The system control unit 116 determines the color temperature of the subject light source from the captured image, such as calculating from the result of auto white balance in the imaging unit 101.

  By such control, the faint light of the candlelight is not canceled by the projection of the captured image. The person who is the subject can easily check the state within the shooting angle of view.

  In the low light mode, the system control unit 116 controls to increase the light amount of the light source 113. Further, an edge image as shown in FIG. 5B is generated, and the gradation is inverted to convert the edge portion to black and the flat portion to white. FIG. 5C shows an image example in which the gradation is inverted.

  By such control, the area of the white pixel portion in the image is widened, and the influence of the reflected light on the subject is increased. As a result, it is possible to shoot brightly even in a dark scene, and the person who is the subject can easily check the state within the shooting angle of view.

  In the night view mode, the system control unit 116 controls the light amount of the light source 113 to decrease. The image processing is the same as that during standard projection. Thereby, it can reduce that projection light reflects on a projection surface and affects a to-be-photographed object.

  In the landscape mode, the system control unit 116 controls to increase the light amount of the light source 113. Further, the projection optical system 115 is controlled to change the zoom to the telephoto side. Further, the projection system image processing unit 111 controls to increase the contrast of the image. An example of projection of an image subjected to these processes is shown in FIG. Since the zoom is changed to the telephoto side, the size of the image is reduced as shown in FIG. However, since the light collection efficiency for a certain light source increases and the contrast increases, it is possible to project more clearly even in bright places such as during landscape photography. The person who is the subject can easily check the angle of view from the projected image.

  As described above, in this embodiment, it is possible to perform image projection that is effective for assisting photographing without impairing the atmosphere of the subject.

  Although four imaging modes were illustrated as an imaging mode, it is not limited to these. Any imaging mode may be used as long as the projection parameter is controlled according to the imaging mode.

  The content of the projection control for each imaging mode is not limited to the content described in the embodiments. For example, processing such as increasing the contrast of the projected image in the night view mode may be added.

  Although the configuration in which the imaging unit 101 and the projection unit 110 are integrated has been described as an example, a configuration in which the imaging unit 101 and the projection unit 110 are separated may be employed.

  In any imaging mode, an image is projected. However, for still image shooting, the above-described control may be performed only at the timing of metering for determining exposure and white balance, or when the shutter is released. .

  A second embodiment of the imaging apparatus according to the present invention will be described. FIG. 6 shows a schematic block diagram of the second embodiment. An imaging scene analysis unit 601 is provided instead of the imaging mode management unit 105 of the embodiment shown in FIG. The captured scene analysis unit 601 determines what kind of scene (night view or landscape) the captured image is. Elements having the same functions as those shown in FIG.

  An operation of projecting a captured image at the time of shooting in the imaging apparatus shown in FIG. 6 will be described. The operation of the imaging unit 101 is the same as that in the first embodiment. That is, a subject image is taken and an image signal is output. At this time, the imaging system image processing unit 104 also outputs the captured image signal to the imaging scene analysis unit 601. The imaging scene analysis unit 601 determines whether the imaging scene is one of four imaging scenes, that is, a night scene, a candlelight, a low light, and a landscape in the present embodiment, by processing described below.

  With reference to FIG. 7, a method for discriminating an imaging scene will be described. 7A to 7C show cumulative histograms of the luminance of the image signal. The horizontal axis is the brightness value, and the brightness increases as going to the right. The vertical axis represents the cumulative frequency, indicating the cumulative frequency from low luminance. In the present embodiment, the imaging scene is determined based on the luminance at which the cumulative frequency exceeds a predetermined threshold value TH. Specifically, assuming that the luminance exceeding the cumulative frequency TH is Y, when Y ≦ Y1, the night scene is determined. When Y1 <Y ≦ Y2, it is determined as low light or candle light. When Y2 ≦ Y, it is determined as a landscape.

  In the example shown in FIG. 7A, since the luminance with the cumulative frequency exceeding TH is smaller than Y1 and the image is extremely dark, it is determined as a night scene.

  In the example shown in FIG. 7B, since the luminance Y with the cumulative frequency exceeding TH is Y1 <Y ≦ Y2, and it is a slightly dark image, it is determined as a low light or candle light scene. Thereafter, it is determined whether the light is a low light or a candle light. For this determination, as shown in FIG. 7D, the ratio of the luminance of the outer side 701 and the inner side 702 of the image is used. When the ratio of the luminance of the inner side 702 to the luminance of the outer side 701 of the image is equal to or greater than a predetermined threshold, it is determined that the scene is a candlelight scene. Conversely, when the ratio of the luminance of the inner side 702 to the luminance of the outer side 701 of the image is smaller than a predetermined threshold, it is determined that the scene is a low light scene. This is because in the case of a candlelight scene, the vicinity of the center of the screen tends to be brighter than the surroundings.

  In the example shown in FIG. 7C, since the luminance Y whose cumulative frequency exceeds TH is higher than Y2, it is determined as a landscape scene.

  The imaging scene analysis unit 601 outputs imaging scene information indicating the determined imaging scene to the system control unit 616.

  The imaging scene analysis unit 601 includes means for detecting a person's face, and outputs the result of detecting the person's face to the system control unit 616 together. Various methods for recognizing a person's face, such as a method for performing pattern matching of luminance signals, have been proposed in the past, and any of these methods may be used.

  The system control unit 616 switches the control of the imaging unit 101 and the projection unit 110 based on the imaging scene information from the imaging scene analysis unit 601 as described below. FIG. 8 shows a flowchart of the switching operation based on the imaging scene information of the system control unit 116.

  In step S <b> 800, the system control unit 616 acquires imaging scene information that is a scene discrimination result from the imaging scene analysis unit 601.

  In step S801, the system control unit 616 switches the imaging mode of the imaging unit 101 based on the imaging scene information determined by the imaging scene analysis unit 601. The imaging mode corresponds to the name of the determined imaging scene. For example, when it is determined that the scene is a candlelight imaging scene, the imaging mode is switched to the candlelight mode. Since the imaging process corresponding to the imaging mode is the same as the contents described in the first embodiment (FIG. 2), detailed description is omitted. When the imaging mode is set, the system control unit 616 performs control on the imaging unit 101 according to the imaging mode.

  In step S <b> 802, the system control unit 616 acquires a detection result of a person's face from the imaging scene analysis unit 601, and determines whether the scene includes a person. If the scene includes a person, the process proceeds to step S803. If the scene does not include a person, the process proceeds to step S807.

  In step S803, the system control unit 616 controls the projection unit 110 to perform normal projection of the captured image. At this time, the system control unit 616 acquires the pre-projection subject image and the post-projection subject image from the imaging system image processing unit 104, and calculates the total value of the luminance differences of the subject before and after the projection.

  In step S804, the system control unit 616 determines whether or not there is a change in the subject by checking whether or not the difference value of the subject before and after projection calculated in step S803 is larger than a threshold value. If the total difference value is larger than the threshold value, it is considered that the projection light has affected the subject and the process proceeds to step S805. On the other hand, if the difference total value of the subject before and after the projection is smaller than the threshold, the system control unit 616 determines that the influence of the projection is small, and proceeds to step S806.

  In step S805, the system control unit 616 performs projection control according to the imaging mode so that the subject is not affected by the projection. The content of the projection control according to the imaging mode is the same as that of the candle light mode, low light mode, night view mode and landscape mode in the table shown in FIG.

  In step S806, the system control unit 616 controls the projection unit 110 to perform normal projection because the subject is not affected by the projection. However, when the image capturing mode is the landscape mode, the projection control is effective even when the image is not affected by the projection. Therefore, the same projection control as in the landscape mode shown in FIG. 4 is performed.

  In step S807, the system control unit 616 performs processing when there is no person on the subject. In this case, the projection is stopped because it is not necessary to show the captured image to the subject.

  In the present embodiment, the imaging scene is determined based on the captured image signal, and the projection parameter is controlled based on the imaging scene. Therefore, the projection control according to the imaging scene can be performed without setting the imaging scene by the user.

  The above-described determination method of the imaging scene is an example, and other methods that can determine the imaging scene can be applied. Further, the imaging scene is not limited to the above four imaging scenes.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the gist thereof.

Claims (8)

Imaging means capable of changing imaging conditions including exposure amount and zoom;
Image processing means for performing image processing on an image captured by the imaging means;
Projecting means for projecting the image processed by the image processing means;
Operating means for instructing one of a plurality of imaging modes;
Control means for controlling the imaging condition of the imaging means according to the imaging mode instructed by the operation means, and controlling either the image processing condition of the image processing means or the projection condition of the projection means. An imaging device,
The image pickup apparatus characterized in that the control means reduces the amount of light projected by the projection means below a reference value in a candlelight image pickup mode. Imaging means capable of changing imaging conditions including exposure amount and zoom;
Image processing means for performing image processing on an image captured by the imaging means;
Projecting means for projecting the image processed by the image processing means;
Means for determining an imaging mode from an image captured by the imaging means;
An imaging apparatus comprising: a control unit that controls the imaging condition of the imaging unit according to the determined imaging mode, and controls either the image processing condition of the image processing unit or the projection condition of the projection unit. There,
The image pickup apparatus characterized in that the control means reduces the amount of light projected by the projection means below a reference value in a candlelight image pickup mode.   The imaging apparatus according to claim 1, wherein the control unit can control a light amount and a size of an image projected by the projection unit.   The imaging apparatus according to claim 1, wherein the control unit controls any one of a contrast, a color temperature, and a contour of the image by the image processing unit.   The control means includes means for detecting whether or not a person is included in an image captured by the imaging means, and when the person is detected, the imaging condition of the imaging means is determined according to the imaging mode. The imaging apparatus according to any one of claims 1 to 4, wherein the imaging apparatus controls any one of an image processing condition of the image processing unit and a projection condition of the projection unit.   The control means detects a difference between a photographed image by the imaging means before and after the projection by the projecting means when the person is detected in the photographed image by the imaging means and when the person is detected. And calculating means for controlling the imaging conditions of the imaging means in accordance with the imaging mode, the image processing conditions of the image processing means and the projection means The imaging apparatus according to claim 1, wherein any one of the projection conditions is controlled. Imaging means capable of changing imaging conditions including exposure amount and zoom;
Image processing means for performing image processing on an image captured by the imaging means;
A control method for an image pickup apparatus having projection means for projecting an image processed by the image processing means,
Instructing one of a plurality of imaging modes;
A step of controlling any one of the imaging conditions of the imaging means and the image processing conditions of the image processing means and the projection conditions of the projection means according to the imaging mode to be instructed, wherein the imaging mode of the candlelight Then, the method of controlling an imaging apparatus comprising the step of reducing the amount of light projected by the projection means to be less than a reference value. Imaging means capable of changing imaging conditions including exposure amount and zoom;
Image processing means for performing image processing on an image captured by the imaging means;
A control method of an imaging apparatus comprising: a projecting unit that projects an image processed by the image processing unit,
Determining an imaging mode from an image captured by the imaging means;
According to the determined imaging mode, the step of controlling the imaging condition of the imaging means and the image processing condition of the image processing means and the projection condition of the projection means, the imaging mode of candlelight Then, the method of controlling an imaging apparatus comprising the step of reducing the amount of light projected by the projection means to be less than a reference value.

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